1. Field of Invention
The present invention relates to a field of biomass energy, and more particularly to a method for producing synthesis natural gas using a straw gas.
2. Description of Related Arts
As more and more attentions are paid to renewable energy sources, the development and utilization technologies of renewable energy sources have been greatly improved. One of them is to obtain straw gas through gasifying straw after crushing for an application of fuel gas. This production technology for the straw gas is well known, the straw gas generated thereby is a kind of gas mixture which mainly contains carbon monoxide, carbon dioxide, hydrogen, and methane, wherein a content of methane thereof is usually no more than 20% and a calorific value thereof is just between 1000˜2000 kcal/Nm3, which belongs to a low calorific value fuel gas.
Currently, this kind of straw gas has already been used by people for cooking and warming, but efficiency of the energy utilization is low, and the straw resource can not be fully explored. It has been also reported that the straw gas replaces coal for generating electricity, but there are still some limitations due to the low calorific value thereof. The low content of methane seriously restricts the application range of the straw gas, so that it is hard to fully use the huge straw resource.